(()=>{
  // 定义一个接口 
  interface Iperson{
    firstName:string 
    lastName :string
  }

  //输出姓名
  function showFullName (person :Iperson){
   return person.firstName + person.lastName
  }
  //定义一个 对象
  const person = {
   firstName : '东方',
   lastName :'不败'
  }
  console.log(showFullName(person));
})()